About this Website

Welcome to the home of the Extreme Precision Radial Velocity Research Coordination Network (EPRV RCN)! This website is meant to serve as a landing page for the EPRV community where members can come to access or contribute resources such as presentation recordings, software tools / tutorials, graphics & animations, and useful literature references. We're in the early days of development and expect new areas to be created and populated by the community over the coming months.

If there are areas of the website that you're interested in contributing to, we encourage you to engage via the Gitflow workflow outlined on the Website Development page! If you have questions, or resources you'd like to contribute without tackling the github lifestyle, you can reach out to our website oversight team at: eprv.rcn-website [at] jpl.nasa.gov

Not sure where to start? Consider:

• Adding yourself to the public facing RCN Directory so that community members can identify potential new collaborators.
• Adding to the Tutorials page where we're aiming to compile useful examples of code for all areas of EPRV science from data downloads, data reduction, stellar variability analyses, planet fitting, etc.
• Suggesting papers on the EPRV ADS Libraries page.
• Adding figures or animations that you've developed to the Visual Resources page.
• Developing new sections/pages that fit within the EPRV Resources or Professional Development umbrellas (e.g., outlines of how to write compelling EPRV observing proposals or compiling lists of funding opportunities that cover EPRV science or instrumentation).
• Nominating yourself or a collaborator to give an RCN Colloquium.
• Suggesting a topic for a future RCN Workshop.

EPRV RCN Announcements

EPRV RCN Colloquium Series

The next EPRV RCN Colloquium will take place on March 26th, 2026 and feature Dr. Momo Ellwarth [Lowell Observatory] who will present on "Magnetic Activity Diagnostics with LOST using the He I D3 Line"! For connection info, please refer to the EPRV RCN Google Calendar and/or email updates, available to RCN members. And please note that because of daylight savings, this talk will occur one hour earlier than normal in the UK and European time zones!

Abstract: Magnetic activity remains one of the dominant sources of noise in extreme precision radial velocity (EPRV) measurements, limiting our ability to detect low-mass exoplanets. Observations of the Sun as a star provide a unique laboratory for disentangling activity-driven variability from true Doppler shifts, as the underlying physical processes can be studied in spatially resolved and disk-integrated observations simultaneously.
In this talk, I will present an overview of the Lowell Observatory Solar Telescope (LOST), which has been observing the integrated Sun since 2020 at a spectral resolution of R ≈ 137,500. These observations enable direct investigations of how solar magnetic features imprint on Sun-as-a-star radial velocities and spectral line shapes. The focus of this talk will be on recent work exploring the He I D3 line as a diagnostic of magnetic activity. Formed in the upper solar atmosphere and strongly linked to chromospheric magnetic structures, He I D3 shows promise as a complementary activity proxy to photospheric indicators.
I will also present some initial results from a multi-year bisector analysis of selected spectral lines, highlighting how line-shape variations may provide additional insight into magnetic activity and its impact on radial velocity measurements.

RCN Overview

The EPRV Research Coordination Network (RCN), sponsored by NASA's Exoplanet Exploration Program, aims to support increased communication and collaboration within the radial velocity community as we work towards the goal of obtaining robust mass measurements for Earth analog planets.

Membership is open to the community and we invite participants from all corners of the RV community and related fields, including but not limited to: observational efforts, instrumentation, data analysis techniques, solar studies, and stellar variability mitigation.

Sign up for the RCN using this Google form. Membership provides access to the RCN mailing list, Google Calendar, Slack workspace, and Google Drive.

Note: All members of the EPRV RCN will be required to follow our Code of Conduct.